Protein kinase biochemical properties

Shiao, M.-S. Drong, R.F. Porter, J.W. The purification and properties of a protein kinase and the partial purification of a phosphoprotein phosphatase that inactivate and activate acetyl-CoA carboxylase. Biochem. Biophys. Res. Commun., 98, 80-87 (1981)... 

TSUKUDA M, ASAOKA Y, SEKIGUCHI K, KKKAWA U, NISMZUKA Y. Properties of protein kinase C subspecies in human platelets. Biochem Biophys Res Commun 155 1387-1395,1988. 

The sensitivity to Ca2+ and diacylglycerol and specific binding of phorbol esters has been considered for a long time to be the main characteristics of protein kinase C enzymes. Molecular cloning techniques and biochemical work, however, revealed that protein kinase C is a large kinase family that includes a variety of isoenzymes with very different regulatory properties (see below). 

Outline of the cellular events that result in the activation of protein kinase C (PKC). The enzyme apparently exists in at least two states. Recent sequence work indicates that it has a Ca -binding site of the EF-hand type. When no Ca " ion is bound, and when the concentration of diacylglycerol (DG) in the inner layer of the plasma membrane is low, the kinase exists in a low-activity form, possibly dissociated from the membrane. When a hormone binds to a plasma-membrane receptor (R), cleavage of phosphoinositol into 1,4,5-1P3 and DG is induced. The latter lipid may bind to and activate the calcium-loaded form of PKC. The active form of protein kinase C will now phosphorylate other cytoplasmic proteins, and in this way modify their biochemical properties. R = receptor PL-C = phospholipase C G = a GTP-binding protein that is assumed to act as an intermediary between the receptor and the membrane bound PL-C. 

Cyclic AMP modulates a great number of complex metabolic reactions, gluconeogenesis, lipogenesis, mitosis, etc. One may wonder how one single compound can be responsible for such a variety of biochemical changes in the cell. Specificity is, in part, determined by the hormonal receptor at the surface of the cell membrane and by the enzymic mosaic of the target cell. But are there other common denominators to the action of cAMP in all cells Protein kinases have been proposed as the common target of cAMP. Little is known about the molecular properties, specificities, and effectors of protein kinase. 

Biochemical Applications. Cellulose phosphate paper (P81), also called phosphocellulose paper, has been used for enzyme assay applications (76). As with many other applications of cellulose phosphate, the ability of the material to act as an ion exchanger is the key property that leads to its use in enzyme assays. Cellulose phosphate paper quantitatively binds small peptides that contain at least two basic residues and a free amino terminus. This allows for protein kinase assays to be performed and P-labeled cofactors [y- P]ATP and nonpeptidic byproducts [ P]Pi to be washed away (77). 

Stanwell, C., Gescher, A., and Watters, D. (1993) Cytostatic and cytotoxic properties of the marine product bistratene A and analysis of the role of protein kinase C in its mode of action. Biochem. Pharmacol, 45, 1753-1761. 

Wang, X.-L. Akhtar, R.A. Abdel-Latif, A.A. Purification and properties of D-myo-inositol 1,4,5-trisphosphate 3-kinase from bovine iris sphincter smooth muscle effect,s of protein phosphorylation in vitro and in intact muscle. Biochem. J., 308 (Pt 3), 1009-1016 (1995)... 

Hill, R.D. and Laing, R.R., Specific reaction of dansyl chloride with one lysine residue in rennin, Biochim. Biophys. Acta 132, 188-190, 1967 Chen, R.F., Huorescent protein-dye conjugates. I. Heterogeneity of sites on serum albumin labeled by dansyl chloride. Arch. Biochem. Biophys. 128, 163-175, 1968 Chen, R.F., Dansyl-labeled protein modified with dansyl chloride activity effects and fluorescence properties. Anal Biochem. 25, 412M16, 1968 Brown, C.S. and Cunningham, L.W., Reaction of reactive sulfydryl groups of creatine kinase with dansyl chloride. Biochemistry 9, 3878-3885, 1970 Hsieh, W.T. and Matthews, K.S., Lactose repressor protein modified with dansyl chloride activity effects and fluorescence properties. 

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